Swivel seat



Sept. 21, 19.43.

A.'E. DAVIES SWIVEL SEAT Fil ed Nov. 22, 1938 2 Sheets-Sheet. 1

Sept. 21, 1943. A. a DAVIES 1 I v v2,329,697

- SWIVELSEAT Filed Nov. 22, 193B 2 Sheets-Sheet 2 later, and thereforethe pedestal must be properly oriented at the time of installation. Ap-

proximate orientation of the pedestal relative to the lunch counter orother object with which the chair may be associated, is effected byrotating the base 1 into desired position before securing it to thefloor with bolts of screws. However, it is often not convenient toexactly orient the base I prior to securing it to the floor, and Itherefore provide means for limited rotary adjustment of the columnfirelative to the base I. To this end (referring to Figs. 8 and 9,'as wellas to Fi-g."2), the bottom wall l2 of the column 6 is provided with apair of downwardly projecting lugs I8 symmetrically disposed onoppositesides of a central vertical plane of the column, and the base!is provided with a pair of threaded recesses [9 receiving screws 20,which project from the inner end of the recesses l9, and contact withthe lugs I8 on the .column. Obviously, by'oppositely shifting thescrews20, the column may be rotatablyadjusted with respect to the base 1 andwhen both screws are tightened up against the lugs i8,- any furtherrelative rotation between the column and base is positively prevented.In practice, the bolt I6 is slightly'loosened, the screws 20 are turnedto orient the columnsto the proper position, and then the boltIGtightened. v V V The construction disclosed in Figs. 2 to? geomprisesa swivel mechanism completely contained L within an oil-tight housingjz,Which housing 22 is tubularin form and'is' suspended within the column6. Thus referring to Fig, 2, the upper end of the tubular housing 22,hereinafter referred to as a tube, is internally threaded and receives athreaded plug member 23, which is shown in perspective in Fig. 4. Thetube 22 is suspended from the plug member 23 by virtue of the threadedconnection therebetween, and the plug 23 in turn is supported by thecolumn 6. a

The column 6 is provided with cylindrical inner bearing surfaces 24,which snugly receive the tube 22 and prevent anytilting or radialmovement of the latter. However, the entire vertical forces applied tothe tube 22 are transferred through the plug member 23 to the column 6.Thus the upper end of column 6 is enlarged to a diameter substantiallygreater than the diameter of the tube 22, defining shoulders onwhichwings26 of the plug member 23 rest. The contaoting surfaces of theshoulders in the column 6 and on the wings 26, instead of being flathorizontally, are inclined, as shown to best advantact of vertical edgesurfaces 21. on the wings against juxtaposed vertical surfaces 28 on thecolumn 5. However, the resistance-to movement afforded by the frictionbetween the supporting shoulders on.the column 6 and the supportedshoulders on the Wings 26, is ordinarily sufficient to prevent, themovement continuing until the surfaces 21 contact against the surfaces28.

To furtherlprovide for increasing the resistance to rotation of themember 23 relative to the tage in the developed view of Fig. 6, in whichview the lower contacting surface of each wing 26 is substantiallywedge-shaped and the cooperating supporting surface on the column 6 issimilarly shaped. It will be observed that by virtue of thesewedge-shaped contacting surfaces the member 23 and the tube 22 willnormally remain ina fixed position of rotation relative to the column 6.However the supporting shoulders on the column are widercircumferentially than the shoulders on the wings 26 so that limitedrotation of the tube 22 relative to the column,

column 6 prior to contact of the surfaces 21 and 28, each shoulder onthe column 6 comprises a pair of central flat intersecting surfaces 29which merge at their outer ends into flat surfaces 30, which lattersurfaces are steeperthan the surfaces 29. The wings 26 have a pair ofintersecting surfaces 3| having the same'inclination as the" surfaces29, but being shorter than the latter. 7

These surfaces 3| merge into outer flat surfaces 32 which have the sameinclination as the surfaces 30, i. e., surfaces 32 are parallel tosurfaces 30, just as the surfaces 3| are parallel'to the juxtaposedsurfaces 29; It is obvious, by virtue of the fact that the surfaces 3|are shorter than the surfaces 29, that the juxtaposed surfaces 30 and 32are normally spacedfrom each other sothat they do not function torestrain initial rotary movement of the wings 25; such initial movementis restrained only bycontact-between the surfaces-29 and 31. Theinclination of the-surfaces 29 and 3] is such as to ordinarily restrainrotationbf the member 23 relative to the column 6. However, should astrong torque be applied to the member 23 so that the friction betweenthe surfaces 29 and 3| is insuflicient to restrain movement, then whenthe movement continues a short distance, the surfaces 30 and 3 2 will bebrought together and these surfaces, because of their greaterinclination-from the horizontal, oppose increased resistance to furtherrotary movement and usually function to stop the motion'prior to contactof the vertical surfaces 21 and 28.

Obviously the cooperating surfaces of the wings 26 andthe column omightbe curved to provide continuously increased resistance to motion.However, an advantage of employing the cooperating flat surfaces 3I29,3032 is that they provide surface contact of relatively large area, sothat wear is reduced and thelife of the parts lengthened. Ifcontinuously curved surfaces were employed, the surfaces on the columnmember 6 would have to have a larger radius of curvature than thecooperating surfaces on' the wings 26 and-hence there would be only linecontact between the cooperating surfaces, resulting in excessive wearand. relatively rapid deformation of th'e'surfaces.

The structure described involving the wing members 26 and thecooperating supporting surtively rigid: with nespect-gtoi the.- tube-22;: thus. it;

may be: provided. with. an. enlarged; rib; or shot-1'1;-

der 3&- which fitssnuglywithim the: tube to prevent; any radish motion.of the: lower end. of the: stem withzrespect to the. tube. At-its. lowerend; the stem 35 terminates: in a cam surfacewhich; consists ctatlowermost convex orwedge-shaped: surface. 31' which. merges: at: its:upper ends. into.- straighhvertical surfaces: 38'... At their upper'ends, the vertical. surfaces; 38. merge into con-- ical surfaces. 312a,which extend upwardly and toward each.- other, terminating: at aihi'ghpoint diametrically opposite the apex of' the surtace 3J2 Positionedimmediately below the stem 35) isarotary cam member Mikhail-ins arrupper cam surface: complementary to the cam surfaces on the'lower end ofstem 35, previously described This cam member 411 is looselyfitted in.the tube 22- and 'isguided for vertical movement. by the spindle, whichsupports the seat I.

This spindle 3' is: cylindrical throughout its upper portion. and issnugly rotatabl yfittedi in. a

central bore 42 in. the body member 23, the cylindrical portion of thespindle 3 extending substant'iallythrough the stem 35 of the menuher23".

At its lower end, the spindle or stem 3"- ismade square incross sectioninstead of" circular. The square-portion of the stem fits snuglyin asquareif aperture 43 in: the member 40 so that the latter is constrainedto rotate with the stem 3", but the stem is free to move verticallythrough the cam member. The lower end of the stem 3restsupon and issupported by a ball 44 which in turn is supported ona helical spring 45,the lower endof the spring resting on the bottom wall of the tube 22-and being supported thereby. A seat member 46 may be provided betweenthe upper end of the spring; 45 andtheball M. A

relatively light helical spring- 41 is' normally compressed between theseating member 4 5 and" thelower end of the cam member; the solefunction of this spring 41 being to maintain contact between the camsurface on the member and thecam surface on thelower end' of stem 35'. p

The spring 15 is of such stiffness that it does not compress in responseto the normal weight of the seat I-, but is compressed bytheaadditionalweight of an occupant on the seat. Therefore, when the seat isunoccupied, it is maintained in: the uppermost position shown in Fig. 2,in whichv position the ball 44 not onlyrests against the} lower en-dofthe stem 2'4 butalso rests against the lower endofthe cam member' iii'so that the relatively stifi spring -65 is efiective to urge the camsurfaces together. This spring force is suchas to. cause the seat torotate into and assume the position shown Fig. 2; in which thecomplementary portions of'the cam surfaces on the members 35-? and t9are juxtaposed to each other. This is the. normal. position of the seat.If theseat: is turned away from this normal position, the rotation ofthe cam member 3h: relative to. the cam surface on the lower end of stem35., forces the member 4i downwardly, thereby further compressine thespring 45; Atthe same time, the spindle 3 follows the ball- Mdownwardly. If the seat is turned far enough, it will cause oneoftheverticalsurfaces 38' on the stem member 35'- to be engaged by one ofthe com-pie mentanr terti al surfaces; 4-8 on. the; am me ber 4a; therby preventin ans fiurth a iv r ta. tion. between; those pa ts:hereafter, if the rotary tome; is suifici ntlr reat, th nt a sembly'including the tube 22 will be rotated to movathe wing! members 26relative to the columne iii-the:- manner-previously described. Whenthemtary tome: is removed. from the seat, the entire assembler, inclu intube it: is restored to normal.. position with: respe to: the column6-,. srauitm. and the snihdlefi: is restored to normal po itionwith,respect, to; the. tube 227, by the force of: the, shrine Whichinrerexpanding causes member 48 to slide along the cam surfiaces. on thestem ht; into the;. normalv position. shown in Fi .2:

It is: desirable that the mechanism positively restore. the; seat to;normal, position when it is. umzccuried, ermit relatively ree.- swivelvaction when the'seatis occupied. Such a r sult. is: presided with; thestructure d scrib d-- 1 Thus reterring: to Fig, 3-, when the Weight. ofair occu hant; is on; the seat; It, the spring #5 is camhrcssed. by thespindle h and the ball 4-4! is carried; 01st: of contactwith the;member. 4E3. Therefiorethe only-upward force.- acting. upon the cam,member 414) that exerted; by the relatively weak: all As hreviouslystated, spring 4'1 is; preterablybarelystrong. enoughto support;thewei'sht. or the cam; member w. Therefore: the resistance it'presentszto; downward movement of the cam ill in response to rotation of thepindle 3L isnes1ieibleiaud an occupant, of the seat can turn it, eitherdirection without noticing. any

; arrpreciable resistance: to movement as; the in cam. member Mt. andthereafter the force of the springefiective to urge the cam Ml.-upwardly, causing it to.- rotateinto normal position.

As previously mentioned; the.- tube 22 is inoperforate. and-is adaptedto contain lubrieating oil. so that all ofthecontactins S r a aretinually"v lubricated. In order toprevent inter ference or theverticalmovemen ithe cam member Ml... due to. a. dashbot eff he t i rsurface of thelatteris: cut. away, as indicated at 50,. to:providechannels for the oil to by-Pass through. as the; cam moves up anddown.

Furthermoregasthespindle: moves up anddown,

it (ilSTl1EQQS;'0i1f'fIOm.thf lower portion of the tube 2'2, and topermit, escape of such displaced oil, the collarlifi; is. provided; withone or more channels: 5:2,; andrc e or more holes 5 r are providedabove: the collar... for oil tow n an out of a chamber 55.- A vent hole53 is provided in the body member to permit airt flowinto and out ofthechamber 55 asthe oil. level therein falls. and rises with movement ofthe spindle 3. This vent hole 53 may also be. employed, as. anoil fillerhole.

A simpler embodiment of the structure. within. thetube'22. isdiscl'osedin; Fig. 10, in which, parts corresponding to those: in the remaining fiures bearthe same reference num rals with he. fi l-f5 a. InthiSflmQdifiGfiin nnb. the ball. .44 auxr iliary spring 41;are.-e1iminateu,.the spring 45d bearing directly against the cam member40a and the lower 'end of the spindle 3a, instead of being slidablethrough the cam member 40a, is supported thereby so that the cam membermoves down with the spindle. Thus the spindle 3a may have a very shortreduced squared end thereon fitting into the squared aperture in the cam46a. In order to reduce resistance to rotation when an occupant is onthe seat, the spring 45a is preferably supported on an antifrictionbearing 60 in the bottom of the tube 22a. It is to be understood thatsuch an antifriction bearing may also be employed in the structure shownin Fig. 2, although it is not so necessary there because of theinterpositioning of the ball M, which itself offers low resistance torotation relative to its contacting members. Of course, if desired, anantifriction bearing can be provided at the top of the spring instead ofat the bottom thereof, in the modification of Fig. 10.

In the operation of the modification shown in Fig. 10, when the seat isoccupied, the spindle 3a moves down to compress the spring 45a, and theinclined surfaces of the cam member 4% are carried clear of thecooperating complementary surfaces on the stem 35a so that there isnorestoring force. However, when the occupants .weight is removed from theseat, the full force of the spring 25a is effective to urge the camsurfaces together, causing them to slide into the position ofequilibrium shown in Fig. 2, the cam surfaces in the modification shownin Fig. having the same shape as those shown in Fig. 2.

Although for the purpose of explaining the invention two specificembodiments thereof have been described in detail, it is to beunderstood that the numerous changes may be made from the particularstructure shown without departing from the invention, which is to belimited only to the extent set forth in the appended claims.

I claim:

1. A swivel seat comprising a seat member, pedestal means, a spindledepending from said seat member into the pedestal member, a first cam insaid pedestal means having a downwardly facing cam surface, a second cambelow said first cam and adapted when urged upwardly against said firstcam to be rotated thereby into a predetermined position, said spindleextending through and being vertically slidable with respect to bothsaid cams and rotatable with re.- spect to the first cam butnon-rotatable with respect to the second cam, spring means for normally,yieldably supporting said second cam against downward movement awayfromsaid first cam, and means including said spindle for depressing saidspring means out of supporting relation with said second cam. inresponse 'to a load on said seat member.

2. The combination described in claim 1, with additional means forsupporting said second cam when said spring means is depressed. by saidspindle. i

3. The combination described in claim 1, with auxiliary spring means ofsubstantially less stiffness than said first-mentioned spring means foryieldably supporting said second cam when said first-mentioned springmeans is depressed by said spindle.

4. A seat comprising a seat member, a pedestal including a base memberadapted to be rigidly anchored to a floor and a column member isingtherefrom, means for normally supporting said seat member on said columnin predetermined position of orientation with respect thereto, means forsecuring said column member to said base member against vertical andlateral movement withrespect thereto, and means for rotatably adjustingsaid column member on said base member and rigidly maintaining it inadjusted position comprising a pair of stop members on said columnmember disposed on opposite sides of the center thereof, and a pair ofscrew members in said base member on opposite sides 'of the centerthereof and adapted to abut against said respective stop members,whereby said column member may be arcuately adjusted with respect tosaid base member by tightening one of said screws and loosening the oter.

5. A swivel seat comprising a seat member, a spindle downwardlydepending therefrom, a pedestal having a recess in the upper endthereof, a casing supported by said pedestal within the recess therein,a plug member positioned in and attached to the upper end of saidcasing, said plug member having a central aperture therein for receivingsaid spindle and having an inclined cam surface on the lower endthereof, the upper portion of said spindle being cylindrical for freerotation in said plug member and the lower end portion being polygonaland of smaller lateral dimension than the upper porion, a movable cammember within said casing below said plug member, having an aperture fornonrotatably receiving the polygonal lower end portion of said spindle,the spindle projecting through said plug member into said movable cammember, and spring means supported by the bottom wall of said casing foryieldably support ing said spindle and said movable cam member, saidspindle being freely movable upwardly with respect to said movable cammember, whereby it may be lifted out of said casing.

6. A seat comprising a seat member, a pedestal,means for supporting saidseat member for rotary and vertical motion on said pedestal and defininga chamber in the pedestal containing oil, and a spindle on said seatmember depending into said chamber, said chamber including means forguidingly supporting said spindle, said spindle displacing oil from thelower part of said chamber in response to downward movement, and meansdefining oil ducts for conducting oil so displaced to the portion ofsaid spindle within the upper part of said chamber to lubricate thesame.

7. In a swivel seat, a seat member, a spindle secured to and dependingfrom said seat, a pedestal having an upstanding hollow column, casingmeans within said column, said casing means having a guide aperture inthe upper end thereof for receiving said spindle, mechanism within saidcasing means for yieldably supporting said spindle for a limited rangeof rotary motion with respect to casing means, and-means supporting saidcasing means in said column comprising cam means on the casing means andcooperating cam means on the column for engaging andsupporting said cammeans on the casing means, said cooperating cam means forcing saidcasing means to move upwardly simultaneously with rotary movement ineither direction from a predetermined normal position of orientationwith respect to said column, said mechanism within said casing meansoffering less resistance to rotary movement of said spindle within saidlimited range of rotary motion than said cooperating cam means offer torelative rotary motion between said casing means and column, wherebysaid mechanism yieldably resists rotary motion of said spindle withrelatively less resistance than said supporting means.

8. A swivel seat comprising a seat member, pedestal means, a spindledepending from said seat member into the pedestal means, a first cam insaid pedestal means having a downwardly facing cam surface, a second cambelow said first cam and adapted when urged upwardly against said firstcam to be rotated thereby into a predetermined position, said spindleextending through and being vertically slidable and rotatable withrespect to said first cam and movable both vertically and rotatably withsaid second cam, spring means for normally yieldably supporting saidsecond cam against downward movement away from said first cam, and meansincluding said spindle for depressing said second cam out of contactwith said first cam against force of said spring means in response to aload on said seat member, said cams having normally engaged inclinedsurfaces for yieldably permitting rotation of said seat member through apredetermined arc, and having vertical surfaces which interengage andprevent rotation beyond the end of said arc, said vertical surfacesbeing of such length as to interengage in all vertical positions of saidsecond cam.

, ARTHUR E. DAVIES.

